The TTL-232R-3V3 is a USB-to-Serial (TTL level) converter cable which allows for a simple way to connect TTL interface devices to USB. This version of FTDI's USB-to-TTL serial adapter cables has its I/O pins configured to operate at 3.3V levels.

The TTL-232R-3V3 uses a FT232RQ device which is housed inside the USB 'A' connector, and is terminated at the end of a 1.8 meter cable with a 0.1" pitch header socket which provided access to transmit (Tx), receive (Rx), RTS#, and CTS#. These lines all operate at 3.3V levels. Also brought out on the header are Vcc (5V), and GND.